Avoiding or Preventing Verdigris

[Kev888]

My HLT is a converted copper hot water cylinder; nothing goes in it aside from tap water, campden tablets and CRS but it seems to be a little prone to developing verdigris - perhaps because its out in the garage.

It rubs off easily enough, but the tank is too tall to make that very easy around the bottom. Does anyone know of a way of preventing verdigris, or a very easy method of removing it (like a spray or something)?

Cheers
kev

[Kev888]

Or maybe its time I just went with a HDPE bin instead.. then I'd have more flexibility of cleaning stuffs too. But I like the idea of metal because my element switches on unattended in the night, and sooner or later I may cock up and it'll come on when empty or something... I guess i could overcome that with a float switch though.

Cheers
Kev

[Wolfy]

Hot vinegar?: http://www.howtobrew.com/appendices/appendixB.html

[Kev888]

Yes vinegar is very effective, but I've always used it in conjunction with a scrubby pad before; so maybe I should just try spraying and see what happens - if spraying is enough I'll be happy!
(cue the bottom of Kev's HLT slowly dissolving in collected acid...).

Cheers
kev

[boingy]

Can't help you with the verdigris but I can recommend fitting a float switch. I added one to my HLT and, in a flash of inspiration, I wired it in-line with temperature sensor of the controller. When the water drops below a certain level the sensor is disconnected from the controller and the controller enters an error state and turns off the element (and also buzzes annoyingly unless you de-solder the buzzer..). So it saved me having to add more circuitry to cut the power. I was a bit concerned that the switch would affect the temperature readings but it was fine when I tested it.

[Kev888]

Thats most interesting, thanks! I've just been perusing ebay and there seem to be quite a few float switches available so it should be fairly easy to do. Hmm.. theres a lot to be said for going plastic then, and most people rate HDPE to around 85c working temperature so even cautious kev here hasn't really got a problem with it for the HLT..

Although naturally that realisation has come just moments after putting a bid on a stainless tank

Cheers,
Kev

[Kev888]

Well happily I lost the bid, so unless any other stainless bargains come up in the next few months I'm going to 'go plastic'. I may even splash out and get a new barrel instead of a recycled one, but we'll see

The condition to myself for using plastic unattended is to fit a float switch; there seem to be loads on ebay but I found this one that goes to boiling temperature, which if its only going to be needed in a fault state may be useful.

Cheers
kev

[Wolfy]

By the time you get the new bucket, add element, float switch and connections, wouldn't it cost about the same as some of the SS Urns (that I saw in a thread here a week or two ago)?

[Kev888]

Well I was hoping to transfer all the bits from my current HLT so its really just the cost of the tank and some new insulation I was looking at. But actually, maybe I should think it through more - you're right that it would still cost time and money to make, so possibly the savings of a cheap barrel aren't the only factor worth considering.

I can get a 120L (new) HDPE barrel for £24 or even a 220L one (which would avoid the need to top up and re-heat during the mash) for £36. A 100L nordic pot is probably about £70, and just a tad on the small side, though I could manage with a bigger top-up during the mash - maybe the sparge would have to wait a bit longer whilst it re-heated.

However thinking about it, the nordic pot is quite a bit shorter than the rather tall narrow HDPE barrels, so I 'may' have enough head room to keep the sparge liquor gravity fed using a Nordic. If I can avoid the need to pump then the extra cost of the pot would be well worth it. In fact the same may apply to the tall HDPE mash tun that I started building a while back too... possibly thats a false economy if it introduces pumps etc..

Hmm, you have me thinking again now

Cheers
Kev

[Wolfy]

[quote="Kev888"]Hmm, you have me thinking again now
/quote]
I just can't help thinking ... SS >>> Plastic.

[Kev888]

Heh heh, its strange how stainless always seems to work out much better

I've a small dilemma now though, as I did some calculations this morning. It appears that if I went with 100L nordic pots for both the HLT and MT upgrade I could keep at least part of the system gravity fed but it would be a bit tight if I wanted the option to batch sparge and I'd have to carry on topping up the HLT and re-treating the sparge liquor during the mash, or I could go with plastic and get all the capacity I wanted at very little cost but I'd have to introduce at least one pumped stage. Decisions decisions!

Cheers
kev